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The Single UNIX &reg; Specification, Version 2<br>
Copyright &copy; 1997 The Open Group

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<h4><a name = "tag_001_014_396">&nbsp;</a>NAME</h4><blockquote>
df - report free disk space
</blockquote><h4><a name = "tag_001_014_397">&nbsp;</a>SYNOPSIS</h4><blockquote>
<pre><code>

df <b>[</b>-k<b>][ </b>-P|-t<b>][</b><i>file</i>...<b>]
</b></code>
</pre>
</blockquote><h4><a name = "tag_001_014_398">&nbsp;</a>DESCRIPTION</h4><blockquote>
The
<i>df</i>
utility writes the amount of available space
and file slots
for file systems on which the invoking user has appropriate read access.
File systems are specified by the
<i>file</i>
operands; when none are specified, information is written
for all file systems.
The format of the default output from
<i>df</i>
is unspecified,
but all space figures will be reported in 512-byte units, unless the
<b>-k</b>
option is specified.
This output contains at least the file system names,
amount of available space on each of these file systems,
and the number of free file slots, or
<i>inodes</i>,
available;
when
<b>-t</b>
is specified, the output contains the total allocated space as well.
</blockquote><h4><a name = "tag_001_014_399">&nbsp;</a>OPTIONS</h4><blockquote>
The
<i>df</i>
utility supports the <b>XBD</b> specification, <a href="../xbd/utilconv.html#usg"><b>Utility Syntax Guidelines</b>&nbsp;</a> .
<p>
The following options are supported:
<dl compact>

<dt><b>-k</b>
<dd>Use 1024-byte units, instead of the default 512-byte units,
when writing space figures.

<dt><b>-P</b>
<dd>Produce output in the format described in the STDOUT section.

<dt><b>-t</b>
<dd>Include total allocated-space figures in the output.

</dl>
</blockquote><h4><a name = "tag_001_014_400">&nbsp;</a>OPERANDS</h4><blockquote>
The following operand is supported:
<dl compact>

<dt><i>file</i><dd>A pathname of a file within the hierarchy of
the desired file system.
If a file other than a FIFO, a regular file, a directory
or a special file representing the device
containing the file system
(for example,
<b>/dev/dsk/0s1</b>)
is specified, the results are unspecified.
Otherwise,
<i>df</i>
will write the amount of free space in the file system
containing the specified
<i>file</i>
operand.

</dl>
</blockquote><h4><a name = "tag_001_014_401">&nbsp;</a>STDIN</h4><blockquote>
Not used.
</blockquote><h4><a name = "tag_001_014_402">&nbsp;</a>INPUT FILES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_403">&nbsp;</a>ENVIRONMENT VARIABLES</h4><blockquote>
The following environment variables affect the execution of
<i>df</i>:
<dl compact>

<dt><i>LANG</i><dd>Provide a default value for the internationalisation variables
that are unset or null.
If
<i>LANG</i>
is unset or null, the corresponding value from the
implementation-dependent default locale will be used.
If any of the internationalisation variables contains an invalid setting, the
utility will behave as if none of the variables had been defined.

<dt><i>LC_ALL</i><dd>
If set to a non-empty string value,
override the values of all the other internationalisation variables.

<dt><i>LC_CTYPE</i><dd>
Determine the
locale for the interpretation of sequences of bytes of text data as
characters (for example, single- as opposed to multi-byte characters
in arguments).


<dt><i>LC_MESSAGES</i><dd>
Determine the locale that should be used to affect
the format and contents of diagnostic
messages written to standard error
and informative messages written to standard output.

<dt><i>NLSPATH</i><dd>
Determine the location of message catalogues
for the processing of
<i>LC_MESSAGES .
</i>
</dl>
</blockquote><h4><a name = "tag_001_014_404">&nbsp;</a>ASYNCHRONOUS EVENTS</h4><blockquote>
Default.
</blockquote><h4><a name = "tag_001_014_405">&nbsp;</a>STDOUT</h4><blockquote>
When both the
<b>-k</b>
and
<b>-P</b>
options are specified,
the following header line will be written (in the POSIX locale):
<pre>
<code>
"Filesystem 1024-blocks Used Available Capacity Mounted on\n"
</code>
</pre>
<p>
When the
<b>-P</b>
option is specified without the
<b>-k</b>
option,
the following header line will be written (in the POSIX locale):
<pre>
<code>
"Filesystem 512-blocks Used Available Capacity Mounted on\n"
</code>
</pre>
<p>
The implementation may adjust the spacing of the header line
and the individual data lines so that the information is
presented in orderly columns.
<p>
The remaining output with
<b>-P</b>
will consist of one line
of information for each specified file system.
These lines are formatted as follows:
<pre>
<code>
"%s %d %d %d %d%% %s\n", &lt;<i>file&nbsp;system&nbsp;name</i>&gt;, &lt;<i>total&nbsp;space</i>&gt;,
&lt;<i>space&nbsp;used</i>&gt;, &lt;<i>space&nbsp;free</i>&gt;, &lt;<i>percentage&nbsp;used</i>&gt;, &lt;<i>file&nbsp;system&nbsp;root</i>&gt;
</code>
</pre>
<p>
In the following list,
all quantities expressed in 512-byte units
(1024-byte when
<b>-k</b>
is specified) will be
rounded up to the next higher unit.
The fields are:
<dl compact>

<dt>&lt;<i>file&nbsp;system&nbsp;name</i>&gt;<dd>
The name of the file system, in an implementation-dependent format.

<dt>&lt;<i>total&nbsp;space</i>&gt;<dd>
The total size of the file system in 512-byte units.
The exact
meaning of this figure is implementation-dependent, but should
include
&lt;<i>space&nbsp;used</i>&gt;,
&lt;<i>space&nbsp;free</i>&gt;,
plus any space reserved by the system not normally
available to a user.

<dt>&lt;<i>space&nbsp;used</i>&gt;<dd>
The total amount of space allocated to
existing files in the file system, in 512-byte units.

<dt>&lt;<i>space&nbsp;free</i>&gt;<dd>
The total amount of space available within the file system
for the creation of new files by unprivileged users, in
512-byte units.
When this figure is less than or equal to zero, it
is not possible to create any new files on the file
system without first deleting others, unless the process has
appropriate privileges.
The figure written may be less than zero.

<dt>&lt;<i>percentage&nbsp;used</i>&gt;<dd>
The percentage of the normally available space that is
currently allocated to all files on the file system.
This is calculated using the fraction:
<pre>
<code>
space used&lt;<i>/(.xcm</i>&gt;space used
</code>
</pre>
expressed as a percentage.
This percentage may be greater than 100 if
&lt;<i>space free</i>&gt;
is less than zero.
The percentage value is expressed as a positive integer,
with any fractional result causing it to be rounded to the next
highest integer.

<dt>&lt;<i>file&nbsp;system&nbsp;root</i>&gt;<dd>
The directory below which the file system hierarchy appears.

</dl>
<p>
The output format is unspecified when
<b>-t</b>
is used.
</blockquote><h4><a name = "tag_001_014_406">&nbsp;</a>STDERR</h4><blockquote>
Used only for diagnostic messages.
</blockquote><h4><a name = "tag_001_014_407">&nbsp;</a>OUTPUT FILES</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_408">&nbsp;</a>EXTENDED DESCRIPTION</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_409">&nbsp;</a>EXIT STATUS</h4><blockquote>
The following exit values are returned:
<dl compact>

<dt>0<dd>Successful completion.

<dt>&gt;0<dd>An error occurred.

</dl>
</blockquote><h4><a name = "tag_001_014_410">&nbsp;</a>CONSEQUENCES OF ERRORS</h4><blockquote>
Default.
</blockquote><h4><a name = "tag_001_014_411">&nbsp;</a>APPLICATION USAGE</h4><blockquote>
On most systems,
the &quot;name of the file system, in an implementation-dependent format&quot;
will be the special file on which the file system is mounted.
<p>
On large file systems, the calculation specified for percentage used
can create huge rounding errors.
</blockquote><h4><a name = "tag_001_014_412">&nbsp;</a>EXAMPLES</h4><blockquote>
<ol>
<p>
<li>
The following example writes portable information
about the
<b>/usr</b>
file system:
<pre>
<code>
df -P /usr
</code>
</pre>
<p>
<li>
Assuming that
<b>/usr/src</b>
is part of the
<b>/usr</b>
file system, the following will do the same as the previous example:
<pre>
<code>
df -P /usr/src
</code>
</pre>
<p>
</ol>
</blockquote><h4><a name = "tag_001_014_413">&nbsp;</a>FUTURE DIRECTIONS</h4><blockquote>
None.
</blockquote><h4><a name = "tag_001_014_414">&nbsp;</a>SEE ALSO</h4><blockquote>
<i><a href="find.html">find</a></i>.
</blockquote><hr size=2 noshade>
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UNIX &reg; is a registered Trademark of The Open Group.<br>
Copyright &copy; 1997 The Open Group
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